Realize that in Christianity and Catholicism, adultery is no better or worse than murder. They are both mortal sins.
If society is based on Christian values but doesn’t punish one with the same seriousness as the other, then it is not a society based on Christian values. Similarly, if society forgives one with more charity than the other, then it is still not a society based on Christian values.
I personally am disgusted at the thought of murder, but at the same time I am not so judgmental of pre-marital sex aka adultery. I am afraid that within my distinction between the two I echo a society that heads for decline. Why? I am sure that it will be proven that although people are disgusted by the thought of murder, it is nevertheless closely tied to sex. Sex is life giving, desirable, and ego-affirming, but it is also a condemnation of lesser people. No matter how conscious or subconscious, you have passed judgement on those not worthy for sex. If our hedonistic impulses drive the sexual market in which we lust after sexier, hotter, more beautiful, more dominant, more powerful people- we have also condemned those who are comparatively normal.
Condemnation is worse than death. That is why those who are condemned have no problem embracing death. It would be a step up.